function q = wv_orders(e, n)
% WV_ORDERS  Observed convergence order between successive resolutions.
%
% q(k) = log(e(k-1)/e(k)) / log(n(k)/n(k-1)), and NaN wherever the ratio is not
% a positive finite number.  A second-order method should print numbers near
% 2 once it is resolved.
q = NaN(size(e));
for k = 2:numel(e)
    r = e(k-1) / e(k);
    if isfinite(r) && r > 0
        q(k) = log(r) / log(n(k) / n(k-1));
    end
end
end